Metastable Non-Nucleonic States of Nuclear Matter: Phenomenology
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The Radiochemistry of Tungsten
National Academy of Sciences !National Research Council NUCLEAR SCIENCE SERIES The Radiochemistry of Tungsten — ...—- L. F. C URTISS,Chairman ROBLEY D. EVANS, Vice Chairman NationalBureau ofStandards MassachusettsInstituteofTechnology J.A. DeJUREN, Secretary WestinghouseElectricCorporation C. J.BORKOWSKI J.W. IRVINE,JR. Oak RidgeNationalLaboratory MassachusettsI&tituteofTechnology ROBERT G. COCHRAN E. D. KLEMA Texas Agriculturaland Mechanical NorthwesternUniversity College W. WAYNE MEINKE SAMUEL EPSTEIN UniversityofMichigan CaliforniaInstituteofTechnology J.J.NICKSON Memorial Hospital,New York U. FANO NationalBureau ofStandards ROBERT L. PLATZMAN Laboratoirede Chimie Physique HERBERT GOLDSTEIN NuclearDevelopmentCorporationof D. M. VAN PATTER America BartolResearch Foundation LIAISON MEMBERS PAUL C. AEBERSOLD CHARLES K. REED Atomic Energy Commission U. S.Air Force J.HOWARD McMILLEN WILLIAM E. WRIGHT NationalScienceFoundation OfficeofNavalResearch SUBCOMMITTEE ON RADIOCHEMISTRY W. WAYNE MEINKE, Chai~man HAROLD KIRBY UniversityofMichigan Mound Laboratory GREGORY R. CHOPPIN GEORGE LEDDICOTTE FloridaStateUniversity Oak RidgeNationalLaboratory GEORGE A. COWAN JULIAN NIELSEN Los Alamos ScientificLaboratory HanfordLaboratories ARTHUR W. FAIRHALL ELLIS P. STEINBERG UniversityofWashington Argonne NationalLaboratory JEROME HUDIS PETER C. STEVENSON BrookhavenNationalLaboratory UniversityofCalifornia(Livermore) EARL HYDE LEO YAFFE UniversityofC slifornia(Berkeley) McGillUniversity CONSULTANTS NATHAN BALLOU JAMES DeVOE NavalRadiologicalDefenseLaboratory -
Nuclear Energy Agency Nuclear Data Committee
NUCLEAR ENERGY AGENCY NUCLEAR DATA COMMITTEE SUMMARY RECORD OF THE lWEEFPY-FIRST MEETING (Technical Sessions) CBNM, Gee1 (Belgium) 24th-28th September 1979 Compiled by C. COCEVA (Scientific Secretary) OECD NUCLEAR ENERGY AGENCY 38 Bd. Suchet, 75016 Paris TABLE OF CONTENTS TECHNICAL SESSIONS Participants in meeting 1. Isotopes 2. National Progress Reports 3. Meetings 4. Technical Discussions 5. Topical Meeting on "Progress in Neutron Data of Structural Materials for Fast ~eactors" 6. Neutron and Related Nuclear Data Compilations and Evaluations Appendices 1 Meetings of the IAEA/NDS planned for 1980, 1981 and 1982 2 Progranme of the Topical Meeting on "Progress in Neutron Data of Structural Materials for Fast Reactors " 3 Summary of the general discussion on the works presented at the Topical Meeting TECmTICAL SESSIONS Perticipants in the 21st Meeting were as follows : For Canada : Dr. W.G. Cross Atomic Energy of Canada Ltd. Chalk River For Japan : Dr. K. Tsukada Japan Atomic Energy Research Institute Tokai-blur a For the United States of America : Dr. R.E. Chrien (Chairman) Brookhaven National Laboratory Dr. S.L. Wl~etstone U.S. Department of Energy Dr. 8.T. Motz Los Alamos Scientific Laboratory Dr. F.G. Perey Oak Ridge National Laboratory For the countries of the European Communities and the European Commission acting together : Dr. R. Iiockhoff (Local Secretary) Central Bureau for Nuclear Pleasurements Geel, Belgium Dr. C. Coceva (Scientific Secretary) Comitato Nazionale per 1'Energia Nucleare Bologna, Italy Dr. S. Cierjacks Kernforschungszentrum Karlsruhe Federal Republic of Germany Dr. C. Fort Conunissariat i 1'Energie Atomique Cadaroche, France Dr. A. Michaudon (Vice-chairman) Commissariat 2 1'Energie Atomique Bruysrcs-1.e-ChZtel Dr. -
Creation and Nuclear Reaction Studies Sorption Behaviour of Short
PL9601122 PL9601121 High-Spin Nuclear Target of 178m2Hf: Creation and Nuclear Reaction Studies Yu. Ts. Oganesian1, S.A. Karamian1, Yu. P. Gangrsky1, B. Gorski1, B.N. Markov1, Z. Szeglowski2, Ch. Briangon3, O. Constantinescu3, M. Hussonnois3, J. Pinard3, R. Kulessa4, H.J. Wollersheim4, G. Graw5, J. de Boer5, G. Huber6 and H.V. Muradian7 XFLNR, JINR Dubna, Russia; 2H. Niewodniczanski Institute Nuclear Physics, Krakow, Poland; 3CSNSM, IPN, Orsay, France; 4GSI, Darmstadt, Germany; 6Miinchen University, Germany; 6Mainz University, Germany; 7Kurchatov Institute, Moscow, Russia. Investigations of the hafnium-178 isomers are a new scientific direction promising the devel- opment of a fundamental knowledge both in the field of the nuclear structure and of nuclear reactions. The completed experiments give grounds for hope of obtaining data on the electro- magnetic moments, on the mean radius and the deformation of the 178Hf nucleus in the state 16+, on the wave function structure of this state, as well as to study the influence of the target high spin on the differential cross sections of nuclear reactions, to find and investigate neutron resonances with a high spin, to obtain direct information on the density of the levels in the earlier inaccessible region of the spin and of the excitation energy, to measure directly the parameters of a giant dipole resonance based on the high spin state and to clarify in detail the role of the structure hindrances in nuclear reactions. Sorption Behaviour of Short-Lived W and Hf Isotopes on Ion Exchangers from HC1/HF Solutions in Fast On-Line Experiments D. Schumann1, R. Dressier1, S. Fischer1, St. -
CROSS SECTIONS of (N,P), (N,Α), (N,2N) REACTIONS on ISOTOPES
CROSS SECTIONS OF (n, p), (n, α), (n, 2n) REACTIONS ON ISOTOPES OF Dy, Er, Yb AT En= 14.6 MEV А.O. Kadenko, O.M. Gorbachenko, V.A. Plujko, G.I. Primenko Nuclear Physics Department, Taras Shevchenko National University, Kyiv, Ukraine Abstract The cross sections of the neutron reactions at En= 14.6 MeV on the isotopes of Dy, Er, Yb with emission of neutrons, proton and alpha-particle were studied by the use of new experimental data and different theoretical approaches. New and improved experimental data were obtained by the neutron- activation technique. Present experimental results and evaluated nuclear data from EXFOR, TENDL, ENDF data libraries were compared with different systematics and calculations within codes of EMPIRE 3.0 and TALYS 1.2. Contribution of pre-equilibrium decay was studied. The recommendations on validity of different systematics for estimations of cross-sections of considered reactions are given. 1. Introduction Studies of the nuclear reaction cross sections induced by neutrons provides an opportunity to get information on the excited states of atomic nuclei and nuclear reaction mechanisms [1]. In addition, nuclear reaction cross section data are necessary in applied applications such as the design of fusion reactors protection and modernization of existing nuclear power plants [2, 3]. In particular, they allow to calculate the activity and the degree of radiation damage to structural elements of nuclear reactors [3]. Practical interest in cross sections of nuclear reactions caused by their wide use in experimental nuclear physics methods, such as the method of boundary indicators in measuring the spectrum of neutrons in the reactor core of a nuclear reactor, or neutron activation analysis. -
Toxicological Profile for Tungsten
TUNGSTEN 73 4. CHEMICAL AND PHYSICAL INFORMATION 4.1 CHEMICAL IDENTITY Tungsten is a naturally occurring element found in the earth=s surface rocks. Tungsten metal typically does not occur as the free element in nature. Of the more than 20 tungsten-bearing minerals, some of the commonly used commercial ones include feberite (iron tungstate), huebnerite (manganese tungstate), wolframite (iron-manganese tungstate), and scheelite (calcium tungstate). Tungsten appears in Group VIB of the periodic table. Natural tungsten is composed of five stable isotopes: 180W (0.12%), 182W (26.5%), 183W (14.3%), 184W (30.6%), and 186W (28.4%). Twenty-eight radioactive isotopes of tungsten are known; most of these isotopes have short half-lives. Tungsten forms a variety of different compounds, such as tungsten trioxide, tungsten carbide, and ammonium paratungstate (Penrice 1997a). Information regarding the chemical identity of elemental tungsten and tungsten compounds is located in Table 4-1. 4.2 PHYSICAL AND CHEMICAL PROPERTIES Tungsten has several common oxidation states (e.g., W[0], W[2+], W[3+], W[4+], W[5+], and W[6+]). However, tungsten alone has not been observed as a cation. Tungsten is stable, and therefore its most common valence state is +6. The naturally occurring isotopes of tungsten are 180 (0.135%), 182 (26.4%), 183 (14.4%), 184 (30.6%), and 186 (28.4%). Artificial radioactive isotopes of tungsten are 173–179, 181, 185, and 187–189 (O’Neil et al. 2001). Elemental tungsten metal is stable in dry air at room temperature. Above 400 °C, tungsten is susceptible to oxidation. Tungsten is resistant to many chemicals and is also a good electrical conductor (Penrice 1997a). -
Mass Fractionation Laws, Mass-Independent Effects, and Isotopic Anomalies Nicolas Dauphas and Edwin A
EA44CH26-Dauphas ARI 10 June 2016 9:41 ANNUAL REVIEWS Further Click here to view this article's online features: • Download figures as PPT slides • Navigate linked references • Download citations Mass Fractionation Laws, • Explore related articles • Search keywords Mass-Independent Effects, and Isotopic Anomalies Nicolas Dauphas1,∗ and Edwin A. Schauble2 1Origins Laboratory, Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637; email: [email protected] 2Department of Earth and Space Sciences, University of California, Los Angeles, California 90095 Annu. Rev. Earth Planet. Sci. 2016. 44:709–83 Keywords First published online as a Review in Advance on isotopes, fractionation, laws, NFS, nuclear, anomalies, nucleosynthesis, May 18, 2016 meteorites, planets The Annual Review of Earth and Planetary Sciences is online at earth.annualreviews.org Abstract This article’s doi: Isotopic variations usually follow mass-dependent fractionation, meaning 10.1146/annurev-earth-060115-012157 that the relative variations in isotopic ratios scale with the difference in Copyright c 2016 by Annual Reviews. mass of the isotopes involved (e.g., δ17O ≈ 0.5 × δ18O). In detail, how- All rights reserved ever, the mass dependence of isotopic variations is not always the same, ∗ Corresponding author and different natural processes can define distinct slopes in three-isotope diagrams. These variations are subtle, but improvements in analytical capa- Access provided by University of Chicago Libraries on 07/19/16. For personal use only. Annu. Rev. Earth Planet. Sci. 2016.44:709-783. Downloaded from www.annualreviews.org bilities now allow precise measurement of these effects and make it possi- ble to draw inferences about the natural processes that caused them (e.g., reaction kinetics versus equilibrium isotope exchange). -
Abstract Ultracold Mixtures of Rubidium and Ytterbium
ABSTRACT Title of dissertation: ULTRACOLD MIXTURES OF RUBIDIUM AND YTTERBIUM FOR OPEN QUANTUM SYSTEM ENGINEERING Creston David Herold, Doctor of Philosophy, 2014 Dissertation directed by: Dr. James Porto and Professor Steven Rolston Joint Quantum Institute, University of Maryland Department of Physics and National Institute of Standards and Technology Exquisite experimental control of quantum systems has led to sharp growth of basic quantum research in recent years. Controlling dissipation has been crucial in producing ultracold, trapped atomic samples. Recent theoretical work has suggested dissipation can be a useful tool for quantum state preparation. Controlling not only how a system interacts with a reservoir, but the ability to engineer the reservoir itself would be a powerful platform for open quantum system research. Toward this end, we have constructed an apparatus to study ultracold mixtures of rubidium (Rb) and ytterbium (Yb). We have developed a Rb-blind optical lattice at λzero = 423:018(7) nm, which will enable us to immerse a lattice of Yb atoms (the system) into a Rb BEC (superfluid reservoir). We have produced Bose-Einstein condensates of 170Yb and 174Yb, two of the five bosonic isotopes of Yb, which also has two fermionic isotopes. Flexible optical trapping of Rb and Yb was achieved with a two-color dipole trap of 532 and 1064 nm, and we observed thermalization in ultracold mixtures of Rb and Yb. Using the Rb-blind optical lattice, we measured very small light shifts of 87Rb BECs near the λzero wavelengths adjacent the 6p electronic states, through a coherent series of lattice pulses. The positions of the λzero wavelengths are sensitive to the electric dipole matrix elements between the 5s and 6p states, and we made the first experimental measurement of their strength. -
Detection of Elements at All Three R-Process Peaks in the Metal-Poor Star HD 160617
Published in the Astrophysical Journal A Preprint typeset using LTEX style emulateapj v. 5/2/11 DETECTION OF ELEMENTS AT ALL THREE R-PROCESS PEAKS IN THE METAL-POOR STAR HD 1606171 ,2 ,3 Ian U. Roederer4 and James E. Lawler5 Published in the Astrophysical Journal ABSTRACT We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium, osmium, iridium, and platinum, which have been detected previously. Absorption lines of these elements are found in archive observations made with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. We present up-to-date absolute atomic transition probabilities and complete line component patterns for these elements. Additional archival spectra of this star from several ground-based instruments allow us to derive abundances or upper limits of 45 elements in HD 160617, including 27 elements produced by neutron-capture reactions. The average abundances of the elements at the three r-process peaks are similar to the predicted solar system r-process residuals when scaled to the abundances in the rare earth element domain. This result for arsenic and selenium may be surprising in light of predictions that the production of the lightest r-process elements generally should be decoupled from the heavier r-process elements. Subject headings: atomic data — nuclear reactions, nucleosynthesis, abundances — stars: abundances — stars: individual (HD 160617) — stars: Population II 1. INTRODUCTION in greater abundance during n-capture reactions. The Understanding the origin of the elements is one of the s-process path closely follows the valley of β-stability, major challenges of modern astrophysics. -
EFFECTIVE RESONANCE INTEGRALS of SEPARATED TUNGSTEN ISOTOPES by Donald F. Shook and Donald Bogart Lewis Research Center
-’ ‘ NASATND-3957 6 . 1 - EFFECTIVE RESONANCE INTEGRALS OF SEPARATED TUNGSTEN ISOTOPES By Donald F. Shook and Donald Bogart ’ I <II, Lewis Research Center Cleveland, Ohio 2- NATIONAL AERONAUTICS AND SPACE ADMINISTRATION ~~ ~ For sale by the Clearinghouse for Federal Scientific and Technical Information Springfield, Virginia 22151 - CFSTl price $3.00 EFFECTIVE RESONANCE INTEGRALS OF SEPARATED TUNGSTEN ISOTOPES by Donald F. Shook and Donald Bogart Lewis Research Center SUMMARY Measurements of effective resonance integrals for separated tungsten isotopes en- riched in tungsten 182, 183, 184, and 186 and for natural tungsten were made relative to gold. The effective integrals were determined by using a small homogeneous reactor to measure epicadmium reactivities for samples of various sizes located at the center of the core. For comparison with the reactivity data, relative y-ray activities of cadmium- covered thin samples of gold were also determined. The experimental results were compared with effective resonance integral calcula- tions by using the Nordheim integral method and recently measured isotopic resonance parameters. Agreement between the calculations and experimental results for tungsten 182, 183, and 184 were generally good. However, for the tungsten 186 samples and for thick samples of natural tungsten, the calculations overestimated experimental effective integrals by 10 to 20 percent. For tungsten 186, the use of a radiation width of 44*4 millivolts for the highly scattering 18.8-electron-volt resonance brought calculations and experiment into better agreement. For natural tungsten, the experimental results indicated the presence of overlap effects for resonances of constituent isotopes. INTRO D UCTlO N A reactor design limitation associated with the use of tungsten in high-temperature thermal spectrum reactors is introduced by the relatively large capture cross sections (ref. -
On-Line Separation of Short-Lived Tungsten Isotopes from Tantalum; Hafnium and Lutetium by Adsorption on Ion Exchangers from Aqueous Ammonia Solution
Jointly I,ublished by Elsevier Scie.ce S. A~. Lausanne and J.Radioanal.Nucl.Chem.,Letters Akad?miai Kiod6, Bltdapest 214 (I) I-7 (I 996) ON-LINE SEPARATION OF SHORT-LIVED TUNGSTEN ISOTOPES FROM TANTALUM; HAFNIUM AND LUTETIUM BY ADSORPTION ON ION EXCHANGERS FROM AQUEOUS AMMONIA SOLUTION 1 1 1 1 D. Schumann , R. Dressler , St. Taut , H. Nitsche , Z. Szeglowski2, B. Kubica2~ L.I. Guseva 3, 4 G.S. Tikhomirova3, A. Yakushev~, O. Constantinescu , V.P. Domanov 4, M. Constantinescu 4, Dinh Thi Lien 4, Yu. Ts. Oganessian 4, V.B. Brudanin 4, I. Zvara 4, H. Bruchertseifer 5 I Institute of Analytical Chemistry, University of Technology Dresden, 01062 Dresden, Germany 2H. Niewodniczanski Institut of Nuclear Physics, Krakow, Poland ~Institute of Geochemistry and Analytical Chemistry, Moscow, Russia 4joint Institute of Nuclear Research, Dubna, Russia 5paul-Scherrer-Institute, Villigen, Switzerland Received 17 June 1996 Accepted I July 1996 The title goal was achieved using a DOWEX 50Wx8 cation exchange column saturated with La(OH) 3 and ammonia solution as eluent.>Hf, Ta and Lu were adsorbed on this column, where- as W remained in the solution. This chemical system may be used for fast on-line separa- tions of element 106. INTRODUCT ION Subgroup VI elements form oxo-anions in alkaline solu- tion I , whereas subgroup IV and V elements and lanthanides hydroiyze under these conditions. This might be of inter- 0236 -5 731/76/.[/S ~ J 2,0 Cops I"ight ~'9~6 Ak~ch~nlirli KicaM, Blldapr All t il.,ht$ rest'tied SCHUMANN et al.: ON-LINE SEPARATION OF TUNGSTEN ISOTOPES est for fast on-line separation of element 106 from heavy actinides and element 104 produced simultaneously in heavy ion reactions. -
Fi Oooc U 1999 3 1 / 40
fi OooC PL0002050 ISSN 1425-204X INSTITUTE OF NUCLEAR CHEMISTRY AND TECHNOLOGY SL ¥ u 1999 31/ 40 Please be aware that all of the Missing Pages in this document were originally blank pages EDITORS Wiktor Smuiek, Ph.D. Ewa Godlewska-Para PRINTING Sylwester Wojtas © Copyright by the Institute of Nuclear Chemistry and Technology, Warszawa 2000 All rights reserved CONTENTS GENERAL INFORMATION 9 MANAGEMENT OF THE INSTITUTE 11 MANAGING STAFF OF THE INSTITUTE 11 HEADS OF THE INCT DEPARTMENTS 11 SCIENTIFIC COUNCIL (1999-2003) 11 SCIENTIFIC STAFF 14 PROFESSORS 14 ASSOCIATE PROFESSORS 14 SENIOR SCIENTISTS (Ph.D.) 14 RADIATION CHEMISTRY AND PHYSICS, RADIATION TECHNOLOGIES 17 GENERATION OF RADICAL CATIONS FROM PHENYL, VINYL, AND ALLYL CONTAINING THIOETHERS IN ORGANIC SOLVENTS A. Korzeniowska-Sobczuk, P. Wiśniewski, K. Bobrowski, L. Richter, O. Brede 19 EPR STUDIES OF RADICALS INDUCED BY IONISING RADIATION IN FLUTAMIDE H.B. Ambroż, E. Kornacka, G. Przybytniak 20 THE ROLE OF Cu(I) AND Cu(II) IN DNA DAMAGES H.B. Ambroż, E. Kornacka, G. Przybytniak 21 TEMPERATURE COEFFICIENT OF THE RADIATION YIELD OF THE RADICAL CH3 • CH COf IN CRYSTALLINE ALANINĘ Z.P. Zagórski 22 COMPETITION BETWEEN INTRAMOLECULAR TWO-CENTERED THREE-ELECTRON BONDED (S. • .S)+ AND (S. • .N)+ FORMATION DURING PHOTOOXIDATION OF METHIONINE-CONTAINING PEPTIDES BY THE 4-CARBOXYBENZOPHENONE TRIPLET STATE IN AQUEOUS SOLUTION K. Bobrowski, G.L. Hug, H. Kozubek, B. Marciniak 23 Trp[NH ' +] -Tyr[O ' ] RADICAL TRANSFORMATION IN H-Trp-(Pro)n-Tyr-OH,n = 3-5, SERIES OF PEPTIDES K. Bobrowski, J. Poznański, J. Holcman, K.L. Wierzchowski 25 EPR OF METALS NANOPARTICLES IN MCM-41 MOLECULAR SIEVES J. -
Optical Frequency Measurement and Ground State Cooling of Single Trapped Yb+ Ions
Optical frequency measurement and ground state cooling of single trapped Yb+ ions Peter Blythe March 2004 with updates and corrections August 2005 Submitted in partial ful¯lment of the requirements for the degree of Doctor of Philosophy of the University of London Abstract The thesis describes experiments on single laser-cooled ions of Yb+ in a radiofrequency ion trap. 2 2 The ion is laser-cooled on the 369 nm S1=2! P1=2 electric dipole tran- 2 2 sition, and high resolution spectroscopy of the 467 nm S1=2! F7=2 electric octupole `clock' transition has been performed. The 467 nm transition can be used as an optical frequency standard. To this end, several absolute optical frequency measurements of the F = 171 + 0; mF = 0 ! F = 3; mF = 0 component in Yb have been made with a femtosecond laser frequency comb generator. The comb was referenced to a hydrogen maser which forms part of the clock ensemble used to generate the UTC(NPL) timescale. During the work described in this thesis, the linewidth of the 467 nm probe laser has been narrowed from 4 kHz to 200 Hz, increasing the measurement resolution. The frequency measurements have been supported by a full investigation of the systematic frequency shifts of the octupole transition, including the AC Stark, second-order Zeeman, quadrupole, DC Stark, second-order Doppler and blackbody shifts. Cooling an ion of 172Yb+ to the ground motional state of the ion trap by `EIT cooling' on the 369 nm transition has been investigated, both by numerical simulation and experiment. A new technique for measuring the temperature of a trapped ion without the use of a narrow transition has been developed.